1. does your dvd/cd burning make use of /tmp ? - Is that full of very old junk which can be deleted?2. It may seem strange but do $ du /home -xsh AND $ df -h /home give the same output?If they are very different, it is possible that there may be some files which are still taking up disk space but are no longer accessible.e.g. $ xine bohemian_rhapsody.mp3 &pause it while it plays$ ls -l bohemian_rhapsody.mp3Oh look there it is$ rm -rf bohemian_rhapsody.mp3$ ls -l bohemian_rhapsody.mp3ah hah, it has gonebut unpause xine and find that the data must still be there (and taking up diskspace) because it is playing happily.

I have seen this happen on webservers when a log gets deleted while apache is still up. This file can get very large without being easily detectable. Stopping the process which is hanging on to the file will free up the diskspace.

3. Lastly - and it is a long shot - but $ df -iI have also seen insufficient space messages when the filesystem has run out of inodes. On home system, look for tens of thousands of very small files. On a webserver, look for some joker who has run a script to make a directory, enter it, make a directory, enter it.... and so on .